Answers about:

How can I enter overlapping sections into a track?

Especially tracks with a return circut often follow the same way back, or contain parts of the same track going back. However, due to a Google maps restriction, it is impossible to set markers on an already existing section. The only possible work around consists in placing the markers near the track and then in a second step, drag each individual marker to its final position.

How can I import track-information files?

Add a new track under “MySports/ MyTracks”. In the left column you’ll find the item “upload track” for entering track information in the formats: GPX, TCX or CRS.

Due to a bug in Safari 3.0 you need to add the extension .xml to your files, for example centralparc.tcx.xml. Otherwise the browser won’t transfer the file correctly.

How close should I set the markers on a track?

For precise altitude profile computing, the markers should be set at a distance of max. 100 m. On the other hand, you should not set too many markers. This will slow your device down. The IE 6 browser is sensitive to too many track markers. Most of the tracks show up rather well with less than 500 markers.

How do we benchmark tracks?

Each track is automatically evaluated on a 1 to 10 scale, the more detailed the author’s information, the better the ranking.

The ranking follows the scheme below:

1 point: Indication of location
1 point: Track description (min. 250 characters)
1 point: Directions
1 point: Surface
1 point: At least one sport
2 points: A track created by a route planer or from a GPS-device
1 point: A track with at least 5 markers per kilometer
1 (additional) point: Track with at least 10 markers per kilometer
1 point: 1 photo of the track (function not available yet)

How do we compute the altitude profile?

We use a database containing a matrix with a 90 m grid of the major part of the inhabited continents of the World. This is fairly sufficient in most cases. Only rather flat paths around lakes surrounded by mountains are not covered optimally by this method.

The best GPS-devices record a barometrical altitude measurement. Actually these devices are not very popular. However, we are working on accepting barometric altitude recordings in the future and not overriding them with our own computations.

How does 1-2-sports compute track lengths?

Due to computing, load distances between two track markers are calculated based on an algorithm assuming the Earth is an ideal sphere with a smooth surface (great-circle distance). Elevations or the fact that the Earth is flattened at the poles is not taken into account.

If you want to know the exact procedure, have a look at Wikipedia: http://en.wikipedia.org/wiki/Great-circle_distance

How precisely should I set markers?

You will soon find out that overall track distance is only slightly influenced by setting very precise markers as opposed to less exact settings. But do take care that the markers are set following the trail you want to take and that the lines shown between markers don’t create shortcuts.